Drill-pipe coupling



Feb, 12, 1929. 1,701,885

T. M. HARDESTY DRILL PIPE'COUPLING Original Filed Dec, 25, 1925 Q Q k; NK Z Patented Feb. 12, 1929.

THOM S M. nannnsrrv, or LONG BEACH, oamronma.

DRILL-PIPE COUPLING.

Application filed December 23, 1925, SeIiaI NO. 77,272. Renewed July 9,1928.

This invention relates to improvements in drill pipes'and drill pipetool joints used in drilling wells.

An object of the invention is to provide a drill pipe with ananti-friction bearing. In drilling wells to any considerable depth by arotary drilling outfit, it very. seldom happens that the 'well hole isabsolutely straight. Consequently, the drill-pipe frequently bearsagainst the interior ofthewell casing during the drilling operations andwill frequently wear holes in the casing or sufiiciently weaken it sothat it is very apt to collapse. By providing an anti-friction bearingon the drill pipe at suitable intervals, this wear of the casing isefiectively. prevented.

Another object of the invention is to provide an anti-friction hearingwhich is mount-' ed upon a tool joint, so that it can thus beconveniently mounted u on the drill pipe and can be easily removed 'orrepair or replace-- ment purposes.

With the. foregoing and otherobjects in view which will be made manifestin the following detailed description and specifically pointed out inthe appended claims, reference is had to the accompanying drawings foran illustrative embodiment of the invention, wherein:

Figure 1 is a vertical section through a tool oint mounted on a drillpipe on which the anti-friction bearing of the preferred constructionhas been placed,

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1, 4

gig. 3 is a perspective view of the bearing, an

Fig. 4 is a sectional view illustrating the anti-friction hearing asbeing mounted upon a coupling for drill pipe and constituting a sliht'modification of'the invention. 1

- leferring to the accompanying drawings wherein similar referencecharacters designate similar parts throughout, the invention ispreferably embodied upon a tool joint consisting of a pin section 10 anda box ll which connect the adjacent ends of adjacent sections of drillpipe 12 and 13. On the pin section 10 there is formed an externalshoulder 14, against which is positioned a ring 15. .Rollers 16 havetheir ends reduced to provide pintles 17 which are rotatable in the ring15. Adjacent the threaded end 18 of the pin section there are formedthreads 19. A second ring 20 is slipped onto the pin section andreceives the pintles 21 formed on the lower end of each of the rollers.A looking ring 22 is threaded onto the threads 19, serving to lock therin g 20 in place.- This locking ring may be locked against rotation orunscrewing by one or more set screws 23.

From the above described construction it will be readily appreciatedthat the bearing a heretofore required to rotate the drill pipe.

It will be noted that the bearing is of a larger diameter than any parton the drill pipe, so that it will always be caused to engage theinterior of the well casing, instead of other parts.

In the modification shown in Fig. 4c, the bearingis embodied upon acoupling for drill pipeas distinguished from the tool joint. In

this modification the adjacent ends of adjacent sections of drill pipeare illustrated at 2 1 and 25. Normally these ends are connected as by asingle coupling member or collar 26. In placing the bearing thereon, ashort section of drill pipe or a nipple 27 is positioned between theadjacent ends'24 and 25 and the collar 26 connects the upper end of thenipple 27 to the lower endof the section 24. This. collar provides ashoulder for the upper rin 15 of the bearing, in which the pintles of te rollers 16 are mounted. A second collar 28 is threaded onto the lowerend ofthe nipple 27 and serves to maintain the lower ring 20 inposition. The second collar 28 also serves to connect the lower end ofthe nipple 27 to the drill pipe section 25. In this construction as wellas that illustrated in Fig. 1 the bearin can be easily and quicklyapplied or remove and willeifectively prevent wearing ofthe casing.

It will be understood that various changes in the detail of constructionmay be made without departing'from the spirit or scope of the inventionas defined by the appended ameter of the Wellcasing to provide for free7 passage of theflushing Water and detritus are journaled.

and rings in Which the ends of said rollers 2. A pipe coupling forconnecting drill i e0 eratin Within a Well casin said i e b b7 couplingbut sufficiently smaller than the in terior of the Well casing toprovide for the free passage of the flushing water and detritus, andrings in which the rollers are jour-' naled.

womee 3. A pipe coupling for connecting drill pipe operating Within aWell casing, said pipe coupling having an annular recess therein, twovertically spaced apart rings mounted in said recess, rollers verticallydisposed and journaled in said rings, said rollers'extending beyond theoutside diameter of the remainder of said coupling, there being leftsuiiicient space between said rollers and the interior of the Wellcasing to provide for the free passage of the flushing fluid anddetritus.

In testimony whereof I have name to this specification.

THOS. M. HARDESTY.

slgned my

